<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>

<body>
    <script>
        var a = 2;
        b = 3;
        var n = '2a';
        m = '5b';
        var x = false;
        y = true;
        console.log(a + b); //5
        console.log(a + n); //'22a'
        console.log(a - b + n); //'-12a'
        console.log(a + b + x); //5
        console.log(b + m + y); //'35btrue'
        console.log(a - b + x + y - n + m); //'NaN5b'

        var wages = prompt('请输入工资');
        var money = wages + 3000;
        console.log(typeof wages);
    </script>
</body>

</html>